Here is the test by which the Blair project will be judged

IF ANYONE is qualified by his own political history to walk the third way, it's Frank Field. One of George Orwell's more conventionally minded colleagues on the left once said (admiringly) that Orwell had a unique capacity to make his friends feel uncomfortable. Field is rather like that.

As Orwell was to the fellow travellers of his day, so Field was to much of the conventional Labour wisdom of the 1980s. He stated and restated the link between individual rights and duties that permeates yesterday's Green Paper before Blairism was even thought of. He saw the virtues of compulsory savings for privately provided pensions when the idea was wholly taboo in his own party. And, around the time of Margaret Thatcher's fall in 1990, he thought, as a Labour backbencher, that she shouldn't be pushed out by her ministers and told her so.

Yet this was - and is - exactly the same Field who embodies to an extreme the ascetic ideal of plain living and high thinking, who resigned on a left-wing principle from the Labour front bench to vote against, rather than merely abstain from voting for, the ban on trade unions at GCHQ, and who when he says, as he did in his Commons statement yesterday, that he has learned most about welfare from his own poor constituents in Birkenhead, actually means it.

Recently, of course, this unusual figure has been cast as co-star in one of the great Whitehall soap operas, the Frank and Harriet show. The exceedingly well documented running battles between Field and Harman within the Department of Social Security have provided hours of harmless and not so harmless entertainment for their colleagues. They have abated now, as Harman's demure presence on the Treasury bench yesterday beside Field was intended to indicate. But that won't stop a quite widespread view among the political classes that the most interesting aspect of yesterday's statement is that it was delivered by Field and not Harman and that this means Harman will be sacked from the Cabinet and Field will take her job.

It isn't. It is much more important than that. For all the ritual complaints that it poses at least as many questions as it answers, the 96 pages of Field's Green Paper tell us quite a lot about how and why the Blair government wants to reform welfare. True, the question of how compulsory saving for pensioners should be extended to those who don't do it now will be left to John Denham's policy paper later in the year. Sure, the Green Paper is thin on how alternatives to the state - such as Field's beloved mutuals - can provide social insurance for risks from long-term illness to redundancy. But what is clear is the distinctly Blairite view that, while "The UK needs more welfare not less", it is no longer up to the taxpayer to fund it. And yes, in spelling out how the huge, exponentially rising costs of pounds 11bn worth of housing benefit means tenants aren't interested in the rents they pay and landlords can charge what they like, it admits there aren't easy answers. But it isn't hard to infer that a wholly new system of financing rented housing costs is on the way. And there is quite a lot else lurking in the detail.

Disability is a rather good example. The decision not to means test Disability Living Allowance is a real one, the outcome of a vigorous behind-the-scenes Whitehall debate in which David Blunkett, among others, expressed outrage at some DSS proposals to make it no longer a universal benefit. Yes, the Green Paper hints that more objective medical testing may be needed to support DLA claims - though it also even-handedly points out that only between 40 and 60 per cent of those who need it are claiming it. But the paper has also recognised that if more of the disabled can be encouraged to work, employers will have to halt their wholesale discrimination against them, which is why the newly announced Disability Rights Commission is necessary. Equally it is emphatic on the urgent need to abandon the barmy system under which incapacity benefit is used as a "simple but expensive route for the Government to keep the unemployment numbers down". Instead of a benefit that acts as a positive incentive to stay at home - and which is either paid in full or not paid at all - it proposes a new test, for new claimants, which will allow recipients to keep some benefit and do some work. And savings, the paper firmly promises, will be used to give more support for those too disabled to work.

This matters partly because the costs are huge - Incapacity Benefit costs pounds 7.8bn. But the section on disability also illustrates some of the Green Paper's most important themes. The first, as for the budget, is the virtues of economic independence through work. The old Sixties doctrine that we would end the century with fewer people at work and all of us working less, has no place in Blair-Brown-Fieldism. Another is that universal benefits are here to stay. On the one hand, there is nothing in the Green Paper that stops Gordon Brown taxing DLA for the very well off as he plans to tax child benefit. Redistribution through taxation of benefits is not taboo. But it looks as though ending them altogether, and risking dislocating the prosperous from the tax and benefit system, is. The doctrine that services for the poor mean poor services has largely won against "affluence testing". Thirdly - there is quite a lot to reassure the disabled and those currently receiving incapacity benefit. Which illustrates another theme: the need to build a national a consensus for change. To reform the welfare state between now and 2020, you have to win elections to do it. And if that means moving slowly, so be it.

Governments face a chronic difficulty. If they produce a fixed blueprint and then force through legislation (the poll tax springs to mind) everyone asks why they didn't consult. If they set out the contours of change without filling in all the details, the same critics ask "where's the beef?" Fortunately, the run-up to yesterday's Green Paper illustrates why it was needed. Opening a broad national debate certainly beats sleepwalking into a row on ill- thought-out lone benefit cuts and a lot of terrifying leaks on plans for the disabled. Field is anyway a man for brilliant insights rather than programmes. Blair's own hand can be detected in much of the Green Paper. Wholesale abolition of means testing or a big-bang move to compulsory private pensions isn't what the paper is about. And if Field had to modify some of his more expensive ambitions, that's the price you pay for being in power. But don't believe this is all fine words and little else. Field's statement yesterday set the test by which the long-term failure and success of the Blair project will be judged.